Sonia Sotomayor faces her final public grilling by senators called to weigh her historic and near-certain confirmation as the first Hispanic justice on the US Supreme Court.

Hour after hour of Senate Judiciary Committee questioning since Monday have failed to draw the appeals court judge (55) into the "meltdown" one of her Republican critics said would be needed to derail her nomination.

The panel was to hold its last scheduled hearing at 9.30am (1330 GMT) on Thursday, a critical step before sending the appointment to the full Senate, which was expected to confirm her before the court reconvenes in September.

Democrats dominate the committee and have, at least on paper, the 60 votes needed to overrun any Republican effort in the Senate to stymie President Barack Obama's choice to replace retiring Justice David Souter.

Sotomayor firmly defended her impartiality on Tuesday and Wednesday as Republicans repeatedly used her past comment that a "wise Latina" might be a better judge than a white male as fuel for charges of racial bias.

"I want to state up front, unequivocally and without doubt, I do not believe that any ethnic, racial or gender group has an advantage in sound judging," she said on Tuesday, calling the remark "a rhetorical flourish that fell flat".

She also shied from openly criticising specific alleged "war on terrorism" excesses under George W. Bush's presidency, but pointedly denounced the high court's 1944 defence of World War II-era imprisoning of Japanese Americans.

"It is inconceivable to me today that a decision permitting the detention and arrest of an individual solely on the basis of their race would be considered appropriate by our government," she said.

"A judge should never rule from fear. A judge should rule from law and the constitution," she added, drawing approval from Democratic Senator Russell Feingold, a fierce Bush critic.

On Wednesday, Sotomayor politely but firmly rebuffed questions about her abortion and gun rights views, and declined to say whether the Supreme Court was wrong not to take up a case challenging the legality of Bush's warrantless wiretapping programme.

"I know it must be very frustrating to you" not to get an answer on the wiretapping case, she told Democratic Senator Arlen Specter of Pennsylvania, who replied: "It sure is."

In keeping with tradition, Sotomayor ducked questions on grounds that answering them might require her to prejudge cases she could be called to rule on if she becomes a Supreme Court justice.

The high bench, which is the final arbiter on the US constitution, is called to decide some of the most divisive disputes in US politics and society, including over abortion, gun rights, freedom of speech, and national security.

But Sotomayor said that President Obama had not asked her position on abortion — one of the most volatile issues in US politics — before nominating her seven weeks ago.

"I was asked no questions by anyone, including the president, about my views on any specific legal issue," she told Republican Senator John Cornyn of Texas.

Republican Senator Tom Coburn apologised to Sotomayor for four incidents in which shouting abortion foes disrupted the proceedings.

"Anybody who values life like I do and is pro-life recognises that the way you change minds is not yell at people," said the Oklahoma lawmaker, who argued for "understanding, not condemnation."

"And so, for that, I apologise. I admire your composure," Coburn said in what was an appreciative refrain in the cavernous and chilly committee room.

"You certainly demonstrated your composure and patience and your extensive legal knowledge," said Democratic Senator Patrick Leahy of Vermont, the chairperson of the committee.

"I appreciate the good humor and attitude that you've brought to this," said Republican Senator John Cornyn of Texas.

Sotomayor drew laughter when, in response to Coburn's questions about self-defence rights, she conjured a hypothetical scenario in which he threatened her and "I go home, get a gun, come back and shoot you."

"You'll have lots of explaining to do," he said.

"I'd be in a lot of trouble then," she agreed.

Sotomayor's rise from a poor childhood in New York City to the pinnacle of US judicial life mirrors the remarkable ascent of Obama, who nominated her seven weeks ago.

The Princeton-educated jurist would be the second woman currently on the court, alongside Justice Ruth Bader Ginsburg, and the third after retired justice Sandra Day O'Connor.

AFP

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